Background of the invention

Outdoor rugged surfaces are exposed to the effects of sunlight and moisture resulting in algal growth. Outdoor surfaces such as ceramic tiles, concrete, brick, natural stone and pavement stone surfaces are frequently colonized with algal growth, tile plague and other unwanted growth such as dirt, moss, green pads and the like. Especially during rainy season, the surface of tiles or concrete remain moist for a longer time. Because of these moist conditions, moss growth is increased. Outdoor rugged surfaces especially under damp or wet conditions, are more susceptible to algae and moss or fungal growth. In some cases, symbiotic populations of algae and fungi also occurs on these surfaces.

Outdoor floor and tile surfaces often comprises smaller or larger cracks and crevices, where algae or other unwanted moss growth can have access to fertile soil and grow larger. Once the cracks are filled with algal growth, the algal population becomes larger, especially on top of the paving stones. These algae colonized surfaces, tiled plague and moss growth on outdoor surfaces are generally rinsed away down into the sewer, using pressurized water from the garden hose or gets naturally flushed away during a thunder rinse.

Conventional methods of controlling algal growth on outdoor rugged surfaces comprise the use of mechanical and chemical methods or a combination of both methods. Mechanical methods include sand blasting, grinding, steam cleaning, brushing, scouring and use of blow torches on the surfaces. In most cases, these procedures are cumbersome, labor intensive and rather expensive, and do not always give a desirable outcome. DE1571593 AI (KOVACHY, J.M.) discloses a composition for cleaning and treating stone surfaces, the composition comprising, e.g. 10-44 wt% ammonium bifluoride and 10-20 wt% phosphoric acid, up to 6 wt% of a surface-active agent, and 10-30 wt% corn syrup and water. The compositions may comprise commercial thickeners to increase the viscosity of the composition and surfactants. This composition produces a thin film on the surface of the stone, making it dirt- repellent and contaminant- repellent. The disclosed composition does not used any naturally available extracts against algae growth, or disinfection of hard surfaces. Further, the disclosed composition is unable to inhibit photosynthesis process of a microbe such as algae completely, where these microbes will reproduce and grow again over a period. However, the usage of chemical compositions for cleaning and treating dirt, contaminant, or microbial infected surface are avoided to support the eco-friendly environment.

Chemical methods include coating the surface using oxidizing agents, halogens, special chemicals, solvents, detergents, enzymes or other chemical compounds. However, the coating wears away over time and are not completely weather resistant. Hence, there still exists a need for a composition and method for preventing algal growth on outdoor surfaces such as ceramic tiles, stone, brick and concrete surfaces.

SUMMARY OF THE INVENTION

The present invention relates to a composition for preventing algal growth on outdoor surfaces such as ceramic tiles, natural stone, brick, concrete and pavement surfaces. The composition comprises ammonium hydrogen-fluoride, phosphoric acid, sodium dodecyl benzene sulfonate, 94 volume percent ethanol, crushed fenugreek seed extract, anionic surfactant and water mixed in optimum ratio. In an embodiment, the composition for preventing algal growth on outdoor surfaces, wherein the composition comprises ammonium hydrogen-fluoride in a concentration range between 2 to 15 volume percent; phosphoric acid in a concentration range between 2 to 15 volume percent; sodium dodecyl benzene sulfonate in a concentration range between 0.1 to 1 volume percent; 94 volume percent ethanol in a concentration range between 1 to 5 volume percent; crushed fenugreek seed extract in a concentration range between 2 to 8 volume percent; anionic surfactant in a concentration range between 1 to 3 volume percent; and water in a concentration range between 57 to 87.9 volume percent.

I should be noted that the term "94 volume percent ethanol in a concentration range between 1 to 5 volume percent' is to be understood as the composition for preventing algal growth should comprise between 1 to 5 volume percent of ethanol in a 94 volume percent concentration. I.e. the term should not be understood as the composition for preventing algal growth should comprise 94 volume percent ethanol.

In another embodiment, the composition for preventing algal growth on outdoor surfaces, comprises ammonium hydrogen-fluoride in a concentration of about 5 volume percent; phosphoric acid in a concentration of about 5 volume percent; sodium dodecyl benzene sulfonate in a concentration of about 0.5 volume percent; 94 volume percent ethanol in a concentration of about 2.5 volume percent; crushed fenugreek seed extract in a concentration of about 5 volume percent; anionic surfactant in a concentration of about 2 volume percent; and water in a concentration of about 80 volume percent.

In another embodiment, the present invention relates to method of preventing algal growth on a substrate, the method comprising the steps of: i) providing the substrate comprising an outer surface for receiving an antimicrobial composition, wherein the antimicrobial composition comprises ammonium hydrogen-fluoride, phosphoric acid, sodium dodecyl benzene sulfonate, 94 volume percent ethanol, crushed fenugreek seed extract, anionic surfactant and water; and ii) treating the outer surface of the substrate with the antimicrobial composition, wherein the antimicrobial composition establishes a chemical connection with silicates on the outer surface or coatings on the outer surface to form a solid layer.

BRIEF DESCRIPTION OF DIFFERENT VIEWS OF DRAWINGS

FIG. 1 illustrates algal growth in crevices and cracks in an untreated outdoor surface. FIG. 2 illustrates a solid layer sealing the crevices and cracks in a treated outdoor surface.

DETAILED DESCRIPTION OF THE INVENTION Many prior art studies have proved that fenugreek seeds and their extracts has a unique ability to combat microorganisms such as algae, bacteria, virus, and infections. The usage of plant extracts, for example, saponins comprising extracts from the fenugreek seeds against algae fouling is well known in the art. The existing compositions of the fenugreek seeds with different surfactants and solvents are incapable of the existence of the microorganisms and inhibiting its reproduction effectively for a long duration. The existing composition of fenugreek extracts are unable to inhibit photosynthesis process of the algae completely, where the algae will reproduce and grow again over a period. The present invention discloses an improved method and composition for preventing algal growth, wherein addresses the problem by inhibiting the photosynthesis process in the algae effectively for a longer duration. The duration of the effectiveness of the composition according to the present invention is at least 10 years and it can keep algae away from a treated area for at least 7 years. The present invention relates to methods and compositions for preventing algal growth on hard outdoor surfaces such as ceramic tiles, natural stone, brick, concrete and pavement surfaces. These surfaces are treated with the composition, which essentially comprises of ammonium hydrogen-fluoride, phosphoric acid, sodium dodecyl benzene sulfonate, 94 volume percent ethanol, crushed fenugreek seed extract, anionic surfactant and water mixed in an optimum concentration.

In an embodiment, the composition for preventing algal growth on outdoor surfaces, comprises the following ingredients mixed in effective amounts: ammonium hydrogen- fluoride in a concentration range between 2 to 15 volume percent; phosphoric acid in a concentration range between 2 to 15 volume percent; sodium dodecyl benzene sulfonate in a concentration range between 0.1 to 1 volume percent;

94 volume percent ethanol in a concentration range between 1 to 5 volume percent; crushed fenugreek seed extract in a concentration range between 2 to 8 volume percent; anionic surfactant in a concentration range between 1 to 3 volume percent; and water in a concentration range between 57 to 87.9 volume percent.

The fenugreek seed extract can be prepared using methods known in the art. According to one embodiment, one of the methods for preparing the fenugreek seed extract comprises the following steps of: 1. boiling 250 grams of crushed fenugreek seeds in 5 liters of water for 5 minutes to form a solution; 2. cooling the solution to about 40 degrees Celsius; and 3. filtering the solution to obtain the fenugreek seed extract. Algae colonization, green pads and moss growth generally occur on outer surfaces of ceramic tiles, bricks, concrete and paving stones. These rugged outdoor surfaces may comprise numerous cracks and crevices in which the algal growth flourishes which ultimately leads to slippery surface and results in damage to the structures. FIG. 1 illustrates algal growth 104 in crevices and/or cracks 102 in an untreated outdoor surface 110. The composition of the present invention can be used to treat the surfaces in order to prevent algal growth, tile plague and moss growth. The composition forms a chemical connection with the silicates present in the coating of the surfaces 1 10 resulting in a solid layer 106 which fills the cracks and/or crevices 102 thus preventing algae's access to soil. The solid layer 106 formed over the surface 110 by treatment with the present composition thus prevents algal growth and colonization. FIG. 2 illustrates a solid layer sealing the crevices and cracks in an outdoor surface treated with the composition for preventing algal growth.

In another embodiment, the composition for preventing algal growth on outdoor surfaces, comprises ammonium hydrogen-fluoride in a concentration of preferably about 5 volume percent; phosphoric acid in a concentration preferably of about 5 volume percent; sodium dodecyl benzene sulfonate in a concentration preferably of about 0.5 volume percent; 94 volume percent ethanol in a concentration preferably of about 2.5 volume percent; crushed fenugreek seed extract in a concentration preferably of about 5 volume percent; anionic surfactant in a concentration preferably of about 2 volume percent; and water in a concentration of about 80 volume percent.

In an alternative embodiment, the present invention relates to a method of preventing algal growth on a substrate, the method comprising the steps of: i) providing the substrate comprising an outer surface for receiving an antimicrobial composition, wherein the antimicrobial composition comprises ammonium hydrogen-fluoride, phosphoric acid, sodium dodecyl benzene sulfonate, 94 volume percent ethanol, crushed fenugreek seed extract, anionic surfactant and water; and ii) treating the outer surface of the substrate with the antimicrobial composition, wherein the antimicrobial composition establishes a chemical connection with silicates on the outer surface or coatings on the outer surface to form a solid layer. The substrate may comprise ceramic tiles, bricks, concrete, natural stones, paving stones and the like.

The existing composition or known prior art for preventing algal growth on the stone surface is unable to inhibit photosynthesis process of the algae completely, wherefore the algae will reproduce and grow again over a period. The present invention discloses an improved method and composition for preventing algal growth addresses, which the problem by inhibiting the photosynthesis process in the algae effectively for a longer duration. The duration of the effectiveness of the composition according to the present invention is at least 10 years and it can keep algae away from a treated area for at least 7 years.

The anti-algal effect of the present composition is long lasting and durable. For example, the composition of the present invention blocks the possible growth of algae and other undesirable surface deposits for up to a period of ten years, without any need for re-treatment during this period. Furthermore, treatment with the composition of present invention seals the small microscopic pores between the cracks and crevices on the surface of tiles, bricks, concrete or stones. The sealing layer prevents the ingress of water, and also prevents the treated surface from frost damage, and thereby increasing the lifetime of the paving stones, tiles, concrete and brick surface. The surfaces treated with the composition gets self-cleaned and prevents algal growth, green pad and moss growth on the surface.